Rain Returns Today

General Overview: WIDESPREAD RAIN AND THUNDERSTORMS ACROSS THE EASTERN HALF OF THE COUNTRY THROUGH MIDWEEK, WITH HEAVY RAINFALL AND POSSIBLE FLASH FLOODING CONCERNS IN THE OHIO VALLEY AND NORTHEAST. HURRICANE PRISCILLA THREATENS THE SOUTHWEST COAST OF MEXICO WHILE TROPICAL STORM OCTAVE DEVELOPS IN THE EASTERN PACIFIC. TEMPERATURES WILL BE SIGNIFICANTLY ABOVE NORMAL IN THE NORTHEAST AND GRADUALLY WARMING ACROSS THE CENTRAL PLAINS AND NORTHERN ROCKIES THROUGH THE EXTENDED PERIOD.

EAST:  A significant weather system will impact the Eastern United States through midweek, bringing widespread rain and thunderstorms from the Northeast through the Mid-Atlantic and Southeast regions. A cold front will push through the region Tuesday into Wednesday, with high pressure building in behind it. Areas of heavy rainfall are possible across portions of the Northeast and Ohio Valley, with potential flash flooding concerns. The heaviest precipitation appears focused along the coastal regions from the Carolinas northward through New England. By Wednesday into Thursday, the precipitation will begin shifting offshore as high pressure builds in from the west. The weekend looks to trend drier for much of the region as the frontal boundary pushes well offshore.

Temperature Anomalies:

-Days 1-3: Significantly above normal temperatures across the Northeast and Mid-Atlantic, with anomalies of 6-12°F above normal. The warmest conditions will be concentrated in New England and the northern Mid-Atlantic states.

-Days 4-6: Cooling trend begins as the cold front passes, with temperatures returning closer to normal across most of the region. Some slightly below normal temperatures possible in the Ohio Valley and Great Lakes.

-Days 7-10: Generally near normal to slightly above normal temperatures regionwide, with warming trends returning by day 10.

CENTRAL:  A complex weather pattern will affect the Central United States over the next several days. Rain and thunderstorms will spread across portions of the Midwest and Ohio Valley early in the period, with the potential for locally heavy rainfall. High pressure will dominate the northern Plains initially, before a new frontal system begins to approach from the northwest by midweek. This will bring additional precipitation chances to the northern Plains and Upper Midwest. By late week, a new system develops with low pressure forming in the northern Plains, bringing another round of precipitation to the region. The southern Plains will see scattered thunderstorm activity, particularly across Texas and Oklahoma.

Temperature Anomalies:

-Days 1-3: Near normal to slightly above normal temperatures across most of the region, with cooler conditions in the northern Plains.

-Days 4-6: Warming trend begins across the Plains, with temperatures climbing to 3-6°F above normal, particularly in the central and northern Plains.

-Days 7-10: Significant warming continues with temperatures 6-12°F above normal across much of the central and northern Plains. The warmest anomalies will be focused in the Dakotas and Nebraska.

WEST:  Multiple weather systems will affect the Western United States through the period. Low pressure systems along the Pacific Northwest coast will bring periods of rain and mountain snow to the region. The Southwest will see scattered thunderstorm activity, particularly across Arizona and New Mexico. High pressure centers over Wyoming and Colorado will provide periods of dry weather for the interior West. By midweek, low pressure develops in the Pacific Northwest and northern Rockies, bringing increased precipitation chances to those regions. The Southwest will continue to see scattered thunderstorm activity through much of the period. California will experience varying conditions with some precipitation possible along the coast.

Temperature Anomalies:

-Days 1-3: Below normal temperatures across portions of the Rockies and Intermountain West, with anomalies of 3-6°F below normal. Near normal temperatures elsewhere.

-Days 4-6: Warming trend begins across much of the West, with temperatures climbing to 3-6°F above normal in the interior West and Southwest. Some below normal temperatures persist in parts of California and the Pacific Northwest.

-Days 7-10: Continued above normal temperatures for much of the interior West, with some cooling in the Pacific Northwest. The warmest anomalies will be focused in the central Rockies.

TROPICAL: Hurricane Priscilla is currently located off the southwest coast of Mexico and poses a significant threat to that region. Additionally, Tropical Storm Octave has developed in the eastern Pacific and will need to be monitored for potential impacts. Neither system is expected to directly impact the continental United States at this time, though moisture from these systems could enhance precipitation across portions of the Southwest. There are two areas of low pressure to monitor for future development. The firs is located in the eastern Pacific that has a 30% chance of development in the next 48 hours and a 70% chance in the next 7 days. This system does not poses any immediate threat to the US. The second areas of interest is located in the Atlantic approximately 1500 miles east of the Windward Islands and has an 80% formation chance within 24 hours and 90% chance within 7 days; this system also poses no immediate threat to the US.